Active-matrix organic light-emitting diodes (AM-OLEDs) used in displays including flexible displays enrich viewer's experience of digital content. Generally, compared with another display such as thin film transistor liquid crystal (TFT-LCD) displays, an AM-OLED display is thinner, brighter, has a wider viewing angle, and consumes lower power. The AM-OLED, however, is more expensive, requires good pixel uniformity, and is more difficult to manufacture.
Thin film transistors (TFTs) including polycrystal silicon TFT and metal oxide TFT are good candidates in pixel circuits for AM-OLED TFT displays. TFT substrates for the displays, however, are usually made of glass or plastics that normally cannot endure high temperature such as 600° C. for crystalline processes.
A display comprises a lot of pixels arranged in rows and columns. Existing pixel circuits include many TFTs and thus result in a larger pixel size, lower resolution, and higher power consumption.
Like reference symbols in the various drawings indicate like elements.